A method of rigid constraint and equilibrium control of water resources based on double-layer nested configuration

Abstract

The present invention discloses a method for rigid constraint and balanced control of water resources based on double-layer nested configuration, comprising the following steps: step 1, dividing regional units and determining their economic and social characteristic parameters in future horizontal years; step 2, calculating the water demand threshold of each regional unit under the condition of efficient water saving in a long series of years; step 3, long series calculation of the water supply threshold of each regional unit under conventional and potential scenarios in the future horizontal year; step 4, carrying out the double-layer nested water resource supply and demand combination design of each regional unit in the future horizontal year; step 5, performing double-layer nested multi-water source multi-user multi-objective water resource optimization configuration calculation; step 6, adjusting the economic and social characteristic parameters of each unit in the future horizontal year and determining the optimal control scheme. The method described in the present invention has strong practicality and operability, can provide quantitative technical support for precise management decision-making of water resources, and has important guiding value for the preparation of basin and regional water resources planning and the construction and implementation of water conservancy projects.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrology and water resources, and in particular relates to a water resources rigid constraint and balance control method based on double-layer nested configuration. Background Art

[0002] Water shortage has become a bottleneck problem restricting my country's economic and social development. Taking water resources as the biggest rigid constraint, rationally planning population, urban and industrial development, and strictly controlling and suppressing unreasonable water demand are important ways to manage water resources in the current and future years. Under the rigid constraints of the determined regional water resources development and utilization red line indicators, how to consider the use of red line coordination indicators in a larger range of the basin and realize their distribution among different regions, promote the efficient use of multiple water sources, effectively coordinate production, life and ecological water use, and achieve a balance between local and overall interests has become a key issue that water resources management decision makers urgently need to solve.

[0003] At present, the research on rigid constraints of water resources has attracted increasing attention, but there is still a lack of unified quantitative calculation methods. On the one hand, most studies mainly conduct water resource supply and demand analysis and allocation research from a regional or river basin perspective, which makes it difficult to consider the mutual feedback and synergy between different regions and river basins, and the rigid constraints of water resources are insufficiently reflected; on the other hand, these studies usually focus on economic goals, and insufficiently consider goals such as balanced development levels and social equity. There is an imbalance in the allocation and utilization of water resources in different regions of the basin, which aggravates the contradiction between water resource development, utilization and protection in different regions such as upstream and downstream, left and right banks, etc. Summary of the invention

[0004] The purpose of the present invention is to provide a water resource rigid constraint and balance control method based on a double-layer nested configuration to solve the above technical problems.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention discloses a water resource rigid constraint and balance control method based on double-layer nested configuration, the method comprising the following steps:

[0007] Step 1: Divide the regional units and determine their economic and social characteristic parameters for the future horizontal year:

[0008] Based on the characteristics of water resources and their development and utilization in the study basin, the total population and industrial development, structure and trend, and administrative division factors, combined with the objectives and requirements of basin and regional water resources management, the study basin is divided into several independent regional units, and the economic and social characteristic parameters of each regional unit in the future level year are determined; the economic and social characteristic parameters include urban population, rural population, industrial added value, effective irrigation area of ​​farmland, forest and fruit irrigation area, fish pond water replenishment area, and the number of large and small livestock;

[0009] Step 2: Calculate the water demand threshold of each regional unit under the condition of high-efficiency water saving for a long series of years:

[0010] Based on the economic and social characteristic parameters determined in step 1, combined with the water use indicators under the condition of efficient water conservation, the long series calculates the water demand of each regional unit under the condition of efficient water conservation in the future horizontal year year by year. The specific calculation formula is:

[0011]

[0012] D t，k，1 =G1 k ×L1 k ×0.365

[0013] D t,k，2 =G1 k ×L2 k ×0.365

[0014] D t,k，3 =G1 t，k ×L3 t，k

[0015] D t,k，4 =G2 k ×L4 k ×0.365

[0016] D t,k，5 =G3 k ×L5 t，k

[0017] D t,k，6 =G4 k ×L6 t，k

[0018] D t,k，7 =G5 k ×L7 t,k

[0019] D t,k，8 =G6 k ×L8 t，k

[0020] D t,k，9 =G7 k ×L9 k

[0021] Where D t，k is the total water demand threshold of the kth unit in year t, m 3 ;D t,k，j is the water demand threshold of the jth user in the kth unit in the tth year, m 3; k = 1, 2…K, that is, there are K different regional units; t = 1, 2…T, that is, there are T future horizontal years, such as short-term, medium-term and long-term; J is the number of water users, that is, J = 9; j = 1, 2…9, in order of urban residents, urban public, ecological environment, rural residents, industrial water, farmland irrigation, forestry and fruit irrigation, aquaculture and livestock and poultry breeding; G1 k is the urban population of the kth unit, people; G2 k is the rural population of the kth unit, people; G3 k is the industrial added value of the kth unit, ten thousand yuan; G4 k is the effective irrigation area of ​​farmland in unit k, mu; G5 k is the forest and fruit irrigation area of ​​the kth unit, mu; G6 k is the water replenishment area of ​​the fish pond in unit k, mu; G7 k is the number of livestock in the kth unit, head; L1 k L2 is the per capita water consumption index of urban residents, L / person / day; k is the urban public per capita water consumption index, L / person / day; L4 t,k is the per capita water use index in rural areas, L / person / day; L5 t,k It is the water consumption index per 10,000 yuan of industrial added value, m 3 / 10,000 yuan; L9 t,k L3 is the livestock water use index, L / head / day; t,k is the per capita ecological environment water use index, m 3 / person, L6 t,k 、L7 t,k and L8 t,k They are the net quota indicators per unit area for farmland irrigation, forest and fruit land, and fish pond water replenishment, m 3 / mu;

[0022] Step 3: Calculate the water supply thresholds of each regional unit under the conventional and potential scenarios in the future horizontal year:

[0023] Under the conventional scenario, the threshold of the future horizontal annual water supply of each regional unit is determined by comprehensively considering the water resources endowment, water resources development and utilization status, water conservancy project construction and related water resources management requirements. It can be specifically divided into three categories: surface water, groundwater and unconventional water. The surface water includes local water, transit water and external water. The specific calculation formula is:

[0024]

[0025] In the formula, Sa t,k is the water supply threshold under the normal scenario in the kth unit in the tth year, m 3 ;Sa t,k,iis the threshold of water supply under the conventional scenario for the i-th water source in the k-th unit in the t-th year; I is the number of water sources, I=3, i=1,2…3, in order, it is surface water, groundwater, and unconventional water;

[0026] Under the conventional scenario, the threshold of the future horizontal annual water supply of each regional unit is less than the available amount of water resources and the control red line of water resources development and utilization. The specific calculation formula is:

[0027] Sa t,k，1 =Min(Sla t，k，1 , Ra t，k，1 )

[0028]

[0029] Sa t，k,2 =Min(Sla t，k，2 , Ra t，k，2 )

[0030] Sa t，k，3 =Ra t，k，3

[0031] In the formula, Sla t，k，1 For and Sla t，k，3 are the available surface water and groundwater in unit k in year t, m 3 ;Sa0 t，k，m is the natural runoff of the river in the kth unit in the mth month of the tth year, m 3 , m=1,2.....M, M is the number of months; Sa1 t,k，m is the river ecological flow requirement for the mth month of the kth unit in the tth year, m 3 ;Sa2 t，k，x is the unusable amount of river flood in the kth unit in the xth month of the tth year, m 3 ; x1 and x2 are the start and end months of the river flood season in year t respectively; Ra t，k,1 , Ra t，k，2 and Ra t，k，3 They are the red line indicators of water resources development and utilization of surface water, groundwater and unconventional water in the kth unit in the tth year. Under the long series conditions, this indicator adopts the multi-year average indicator;

[0032] The future horizontal annual water supply threshold of each regional unit under the potential scenario refers to the water supply threshold determined by considering the allocation and application of the reserved overall planning indicators in a larger scope on the basis of the conventional scenario, that is, the reserved overall planning indicators are added to the water supply threshold under the conventional scenario. The specific calculation formula is:

[0033] Sb t，k， =Sa t，k，i +T t，k,i

[0034]

[0035] In the formula, Sb t，k is the water supply threshold of the potential scenario in the kth unit in the tth year, m 3 ; Sb t，k，i is the threshold of available water volume for the i-th water source in the k-th unit in the t-th year under the potential scenario; T t,k，i The reserve overall index for the watershed that can be obtained from the i-th water source in the k-th unit in the t-th year, m 3 ;

[0036] Step 4: Carry out the design of double-layer nested water resource supply and demand combinations for each regional unit in the future horizontal year:

[0037] On the basis of steps 2 and 3, a two-layer nested supply and demand combination design is carried out for each regional unit in the future horizontal year. The inner layer is the basic layer, i.e., the regional level. The supply and demand constraint combination of each unit is the total water demand threshold under the condition of efficient water conservation and the water supply threshold under the conventional scenario. The outer layer is the extended layer, i.e., the basin level. The supply and demand constraint combination of each unit is the total water demand threshold under the condition of efficient water conservation and the water supply threshold under the potential scenario. The inner layer and the outer layer are organically linked through the basin reserved coordination indicators.

[0038] Step 5: Perform double-layer nested multi-water source multi-user multi-objective water resource optimization configuration calculation:

[0039] Based on the design of the double-layer nested supply and demand combination in the future horizontal year of each regional unit, the multi-objective water resources optimization allocation is carried out in layers, mainly including the following steps:

[0040] Step 51: Determine the decision variables:

[0041] The decision variable of the basic layer is the allocation of water volume from different water sources to each user in each regional unit, i.e., Q t,k,i,j , represents the amount of water allocated from the i-th water source to the j-th user in the k-th unit in the t-th year, where t = 1 ~ T; k = 1 ~ K; i = 1 ~ I; j = 1 ~ J; the decision variable of the extended layer is the water resources development and utilization index reserved for the basin that can be obtained by the k-th unit;

[0042] Step 52: Set the objective function:

[0043] The objective function of the base layer is to maximize the economic efficiency of the regional unit, and the calculation formula is:

[0044] f t，a ={f1 t，k}

[0045]

[0046]

[0047] In the formula, f t,a is the objective function of the base layer in year t; f1 t,k is the economic objective function of the kth unit in the tth year, 10,000 yuan; Max() is the maximum value function; GDP t，k，j is the net economic output of the jth user in the kth unit in the tth year, 10,000 yuan; GEa t，k , GEb t，k , GGEC t，k and GEd t，k are the net economic output parameters of agriculture, industry, tertiary industry and living sectors brought by the k-th unit of water use in year t, 10,000 yuan / m 3 ; U t0,k，j is the water consumption of the jth department in the kth unit in the current year, fa, fb, fc, and fd are the allocation coefficients of agriculture, industry, tertiary industry, and living sectors respectively; GEa t0,k , GEb t0,k , GEC t0,k They are respectively the added value of agriculture, industry and tertiary industry brought by the water use of the kth unit in the current year, 10,000 yuan; GEd t0,k is the disposable income of residents in the kth unit in the current year, ten thousand yuan; er is the Engel coefficient, dimensionless;

[0048] The objective function of the extended layer is to maximize the economic efficiency of water resources utilization in the basin, maximize the balance of development level, and maximize the balance of social equity. The calculation formula of the objective function of the extended layer is as follows:

[0049] f t,b ={f1 t , f2 t , f3 t}

[0050] In the formula, f t,b f1 is the objective function of the expansion layer in year t; t f2 is the economic objective function in year t; t f3 is the objective function of the development level balance in year t; t is the social equity equilibrium objective function in year t;

[0051] Step 53: Determine the constraints:

[0052] Determine the constraints, which include water demand constraints of each regional unit, water supply constraints under conventional scenarios, water supply constraints under potential scenarios, ecological flow guarantee constraints, water quality compliance constraints in water functional areas, and non-negative constraints;

[0053] Step 54: Solve using an efficient optimization algorithm:

[0054] The non-dominated sorting genetic algorithm with elite strategy is used to achieve efficient optimization and provide an optimal allocation scheme for water resources with multiple water sources and multiple users.

[0055] Step 6: Adjust the economic and social characteristic parameters of each unit in the future horizontal year and determine the optimal control plan:

[0056] According to the long series of water sources and users in each regional unit, the configured water volume Q is obtained through optimization solution. t,k,i,j , calculate the water intake guarantee rate by user, the specific calculation formula is:

[0057]

[0058] Where P k,a is the water supply guarantee rate of agricultural users in unit k, %, PL k,a is the water supply guarantee rate requirement for agricultural users in unit k, which is greater than 50% or 75%; P k,b is the water supply guarantee rate of the kth unit industrial user, %; PL k,b The water supply guarantee rate requirement for the kth unit industrial user is greater than 90% or 95%; P k,c is the water supply guarantee rate of residents in unit k, %; PL k,c The water supply guarantee rate requirement for the kth unit residential users is required to be greater than 95% or 98%; P k,d is the water supply guarantee rate of the kth unit ecological user, %; PL k,d The water supply guarantee rate requirement for the ecological user in unit k is greater than 50% or 75%;

[0059] If the water withdrawal guarantee rate requirement is not met, the economic and social characteristic parameters of each unit in the future horizontal year are adjusted, and the above steps 2 to 5 are repeated until the configured water volume of each user in each unit meets the water withdrawal guarantee rate requirement. The specific calculation formula is:

[0060] G1 k ′=G1 k ×Min(K1 t，k , M1 t，k )

[0061] G2 k ′=G2 k ×Min(K2 t，k , M2 t，k ,)

[0062] G3 k ′=G3 k ×Min(K3 t，k , M3 t，k ,)

[0063] G4 k′=G4 k ×Min(K4 t，k , M4 t，k ,)

[0064] G5 k ′=G5 k ×Min(K5 t，k , M5 t，k ,)

[0065] G6 k ′=G6 k ×Min(K6 t，k , M6 t，k ,)

[0066] G7 k ′=G7 k ×Min(K7 t，k , M7 t，k ,)

[0067] In the formula, G1 k ′~G7 k ′ are the adjusted values ​​of urban population, rural population, industrial added value, effective irrigation area of ​​farmland, irrigation area of ​​forest and fruit, water replenishment area of ​​fish ponds and number of livestock in the kth unit in the tth year; K1 t,k ~K7 t，k M1 is the adjustment coefficient of urban population, rural population, industrial added value, effective irrigation area of ​​farmland, forest and fruit irrigation area, fish pond replenishment area, and livestock number of unit k in year t, dimensionless; t，k ~M7 t，k They are the maximum limit rate requirements for urban population, rural population, industrial added value, effective irrigation area of ​​farmland, forestry and fruit irrigation area, fish pond replenishment area, and livestock number at the k-th unit management level in the t-th year, dimensionless.

[0068] Furthermore, the regional units described in step 1 are divided according to administrative regions, including provincial, prefecture-level, district, county and township administrative units.

[0069] Furthermore, the specific method for determining the economic and social characteristic parameters of each regional unit in the future horizontal year described in step 1 is: to determine according to the relevant planning data of the economic and social characteristic parameters of each regional unit, and for the lack of relevant planning data, to conduct forecast analysis based on relevant historical data, and the historical data include water resources bulletin, economic and social statistical yearbook, and water conservancy development bulletin; the forecast analysis includes two methods, one is the historical trend extension method, that is, based on historical data, identifying the influencing factors, and predicting the values ​​of various parameters in the future horizontal year through multivariate regression technology; the second is the comprehensive simulation method, based on the identification of influencing factors, by establishing a mathematical model to predict the values ​​of the economic and social characteristic parameters of each regional unit in the future horizontal year, and the data model is a system dynamics model, a fuzzy analysis model or a neural network model.

[0070] Furthermore, the water use index in step 2 is calculated according to the historical trend method, or determined by referring to the "Technical Specifications for Forecasting and Analysis of Water Resources Supply and Demand" and the water use quotas issued by the state or provinces, autonomous regions, and municipalities directly under the central government; the water use index includes two types: one is life and industrial type indicators, including urban residents' per capita water use indicators, urban public per capita water use indicators, rural per capita water use indicators, industrial water use indicators per 10,000 yuan of added value, and livestock water use indicators; the second is ecological and agricultural type indicators, including per capita ecological environmental water use indicators, and net quota indicators per unit area for farmland irrigation, forestry and fruit land, and fish pond water replenishment; the life and industrial type indicators are not affected by rainfall and take fixed values; the ecological and agricultural type indicators are affected by rainfall and need to be adjusted, specifically, in a wet year, a water use indicator with a higher agricultural water demand guarantee rate is selected, and in a dry year, a water use indicator with a lower guarantee rate is selected.

[0071] Furthermore, the economic goal in step 52 is to maximize the per capita added value of all units in the basin, and the calculation formula is:

[0072]

[0073] In the formula, POP t,k is the population of unit k in year t, people; GDP t,k is the added value of the kth unit in year t, ten thousand yuan;

[0074] The development level balance target is to minimize the difference in per capita added value brought about by the development and utilization of water resources in each unit; the Gini coefficient method is used for calculation, and the calculation formula is:

[0075] f2 t =Min(Gn t )

[0076]

[0077] In the formula, Gn tis the Gini coefficient of per capita net economic output of all units in year t, dimensionless; GDPR k POPR is the proportion of the net economic output of the kth unit in the tth year to the total net economic output, dimensionless; k POPL is the proportion of the population of the kth unit in the tth year to the total population, dimensionless; k is the cumulative proportion of the population of the kth unit to the total population, dimensionless;

[0078] The social equity and balance goal is measured by the dispersion coefficient of water shortage rate, that is, the dispersion coefficient of the maximum water shortage rate in each region is the smallest; the calculation formula of the dispersion coefficient of water shortage rate is:

[0079] f3 t =Min(Rd t )

[0080]

[0081] Where Rd t is the dispersion coefficient of water shortage rate of each unit in year t, dimensionless; Sd t is the average water shortage rate of each unit in the tth year, %; Td t is the standard deviation of water shortage rate of each unit in year t, %.

[0082] Furthermore, the water demand constraint in step 53 is: the water volume configured by the j-th user of each unit is not greater than the water demand of the j-th user of each unit under the condition of efficient water saving, and the calculation formula is:

[0083]

[0084] The water supply constraint under the conventional scenario is: the configured water volume of the i-th water source of each unit is not greater than the water supply threshold of each water source in each unit under the conventional scenario, and the calculation formula is:

[0085]

[0086] The water supply constraint under the potential scenario is: the water allocation of each water source in each unit plus the reserved overall planning index of the basin shall not be greater than the water supply threshold of each water source in each unit under the potential scenario. The calculation formula is:

[0087]

[0088] The ecological flow guarantee constraint is: the water consumption of each user in the kth unit in the tth year after the configured water volume meets the requirements of the ecological flow of the river control section, and the calculation formula is:

[0089]

[0090] Where Eflk,t,h is the ecological flow control requirement for the hth section of the kth unit in the tth year, m 3 / s; Eek t,k is the water consumption coefficient of the kth unit in the tth year, dimensionless; h1 is the total number of upstream unit numbers related to the hth section; We t,k,h1 is the discharge requirement of the upstream control section h1, m 3 / s;

[0091] The water quality compliance constraint of the water functional area is: the pollutants discharged into the water functional area meet the pollutant constraints that the water functional area can accommodate, and the calculation formula is:

[0092]

[0093] In the formula, WR t,m,n is the controlled amount of pollutants entering the river in the nth water function zone m in the tth year, t / a; R t,k,j,m is the pollutant emission coefficient of the mth pollutant discharged by the jth user of the nth water functional area from the kth unit in the tth year, dimensionless; C t,k,j,m is the concentration of the mth pollutant of the jth user in the kth unit in the tth year, mg / l;

[0094] The non-negative constraint is that the configured water volume from different water sources in each regional unit to each user is not negative, and the calculation formula is:

[0095] Q t,k,i,j ≥0

[0096] Furthermore, the step 54 of using the non-dominated sorting genetic algorithm with an elite strategy to achieve efficient optimization specifically includes the following steps:

[0097] 1) Data input: Input the data and parameters of the non-dominated sorting genetic algorithm with elite strategy, including objective function, population size, genetic generation, crossover rate and mutation rate;

[0098] 2) Initialize the population and generate the parent population: use a random generation method for the initial values ​​of the decision variables;

[0099] 3) Perform non-dominated sorting and objective function fitness calculation: Initialize the population, calculate the fitness of the objective function of the population, and perform fast non-dominated sorting so that the chromosome gene encoding of the decision variable with high objective function fitness is preserved, and the solution with low fitness is crossover and mutation to generate new offspring to meet the elite strategy, that is, the parent generation and the offspring compete, and the chromosome gene encoding of the decision variable that best meets the objective function is selected and retained. By increasing the crowding degree and improving the population diversity, the optimization efficiency of the algorithm is improved;

[0100] 4) Circular calculation retains elite individuals to obtain the Pareto frontier: the parent and offspring populations are mixed and cyclically calculated to perform crossover, mutation, non-dominated sorting and fitness calculation, and elite individuals with high fitness of the objective function are retained until the genetic algebra conditions are met and the Pareto frontier of the decision variable is obtained;

[0101] 5) Give the optimal solution based on the objective function weight: According to the Pareto frontier, determine the objective function weight and recommend the optimal allocation solution for water resources with multiple water sources and multiple users.

[0102] The beneficial effects of the present invention are as follows: the method of the present invention can effectively coordinate the relationship between different regional units and the entire basin through double-layer nested multi-objective optimization configuration of regions and basins, and maximize the economic efficiency of multi-user and multi-water source utilization at the regional unit level under the red line indicator conditions of water resources development and utilization, and maximize the economic efficiency of water resources utilization, maximize the balance of development levels, and maximize the balance of social equity at the basin level. The method of the present invention has strong practicality and operability, and can provide quantitative technical support for precise management decisions of water resources in basins and different regions, and has important guiding value for the preparation of basin and regional water resources planning and the construction and implementation of water conservancy projects.

[0103] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0104] Figure 1 is a flow chart of the method of the present invention;

[0105] Figure 2 This is a principle block diagram of the method of the present invention;

[0106] Figure 3 It is a Pareto front diagram of the multi-objective function equilibrium in the first embodiment;

[0107] Figure 4 It is a graph showing the algebraic changes of each objective function in the first embodiment;

[0108] Figure 5 It is an optimized allocation diagram of the basin coordination indicators among various cities in Example 1; DETAILED DESCRIPTION

[0109] The present invention discloses a water resource rigid constraint and balance control method based on double-layer nested configuration, such as Figure 1 , Figure 2 As shown, the method comprises the following steps:

[0110] Step 1: Divide the regional units and determine their economic and social characteristic parameters for future horizontal years.

[0111] The division of regional units is the basis and premise for implementing rigid constraints and balanced control of water resources. Taking into account the characteristics of water resources and their development and utilization in the basin, the total population and industrial development, structure and trend, administrative divisions and other factors, based on the availability and reliability of water resources and their development and utilization data, combined with the objectives and requirements of basin and regional water resources management, the basin is divided into several independent regional units, and the upstream and downstream links between these units are established. They are usually divided according to administrative regions, including provincial, prefectural, district, county and township administrative units.

[0112] For the future horizontal year, there are seven main economic and social characteristic parameters for each regional unit, including urban population (G1 k ), rural population (G2 k ), industrial added value (G3 k ), effective irrigation area of ​​farmland (G4 k ), forest and fruit irrigation area (G5 k ), fish pond water replenishment area (G6 k ), the number of large and small livestock (G7 k ). These economic and social characteristic parameters affect the water demand scale of each regional unit. It is necessary to consider the rigid constraints of water resources and carry out balanced optimization control to achieve harmonious development of water resources and economic society.

[0113] The economic and social characteristic parameters of each regional unit in the future year are generally determined based on the relevant planning data of each regional unit. If the regional unit lacks the relevant planning data of the above economic and social characteristic parameters, it can be predicted and analyzed based on historical data such as relevant water resources bulletins, economic and social statistical yearbooks, and water conservancy development bulletins. There are mainly two methods. One is the historical trend extension method, which is based on historical statistical data to identify the main influencing factors and use multivariate regression technology to predict the values ​​of various parameters in the future year. For example, the urban population can be predicted using an exponential model or a logistic model. The second is the comprehensive simulation method, which is based on the identification of influencing factors and establishes mathematical models (such as system dynamics models, fuzzy analysis models or neural network models) to predict the values ​​of the economic and social characteristic parameters of each regional unit in the future year.

[0114] Step 2: Calculate the water demand threshold of each regional unit under the condition of high efficiency and water saving in the future horizontal year in a long series.

[0115] Adhere to the priority of water conservation. Based on the economic and social characteristic parameters determined in step 1, combined with the water use indicators under the condition of efficient water conservation, the long series calculates the water demand of each regional unit under the condition of efficient water conservation in the future horizontal year year by year. The specific calculation formula is:

[0116]

[0117] Dt,k，1 =G1 k ×L1 k ×0.365

[0118] D t,k，2 =G1 k ×L2 k ×0.365

[0119] D t，k，3 =G1 t，k ×L3 t，k

[0120] D t,k，4 =G2 k ×L4 k ×0.365

[0121] D t,k，5 =G3 k ×L5 t,k

[0122] D t,k,6 =G4 k ×L6 t,k

[0123] D t,k,7 =G5 k ×L7 t,k

[0124] D t,k,8 =G6 k ×L8 t,k

[0125] D t,k,9 =G7 k ×L9 k

[0126] Where D t,k is the total water demand threshold of the kth unit in year t, m 3 ;D t,k,j is the water demand threshold of the jth user in the kth unit in the tth year, m 3 ; k = 1, 2…K, that is, there are K different regional units; t = 1, 2…T, that is, there are T future horizontal years, such as short-term, medium-term and long-term; J is the number of water users, that is, J = 9; j = 1, 2…9, in order of urban residents, urban public, ecological environment, rural residents, industrial water, farmland irrigation, forestry and fruit irrigation, aquaculture and livestock and poultry breeding; G1 k is the urban population of the kth unit, people; G2 k is the rural population of the kth unit, people; G3 k is the industrial added value of the kth unit, ten thousand yuan; G4 k is the effective irrigation area of ​​farmland in unit k, mu; G5k is the forest and fruit irrigation area of ​​the kth unit, mu; G6 k is the water replenishment area of ​​the fish pond in unit k, mu; G7 k is the number of livestock in the kth unit, head.

[0127] L1~L9 are water use indicators for different users under the condition of efficient water conservation. These water use indicators can be calculated based on the historical trend method, or can be determined by referring to the Technical Specifications for Forecasting and Analysis of Water Resources Supply and Demand (SL429-2008) and the water use quotas issued by the state or provinces (autonomous regions, municipalities directly under the central government). Specifically, the first is the indicators for living and industrial types, namely L1 k L2 is the per capita water consumption index of urban residents, L / person / day; k is the urban public per capita water consumption index, L / person / day; L4 t,k is the per capita water use index in rural areas, L / person / day; L5 t,k It is the water consumption index per 10,000 yuan of industrial added value, m 3 / 10,000 yuan; L9 t,k The second is the livestock water use index, L / head / day. Under long-term conditions, the water quota of these indicators is usually not affected by rainfall and takes a fixed value; the second is the ecological and agricultural type index, namely L3 t,k is the per capita ecological environment water use index, m 3 / person, L6 t,k 、L7 t,k and L8 t,k They are the net quota indicators per unit area for farmland irrigation, forest and fruit land, and fish pond water replenishment, m 3 / mu. These water use indicators are affected by rainfall and need to be adjusted. Specifically, in wet years, water use indicators with higher agricultural water demand guarantee rates are selected, while in dry years, water use indicators with lower guarantee rates are selected.

[0128] Step 3: Calculate the water supply thresholds for each regional unit under future horizontal year conventional and potential scenarios in a long series.

[0129] Under the conventional scenario, the threshold of the future horizontal annual water supply of each regional unit is determined by comprehensively considering factors such as water resource endowment, water resource development and utilization, water conservancy project construction, and related water resource management requirements. It can be specifically divided into three categories: surface water (including local water, transit water, and external water), groundwater, and unconventional water. The specific calculation formula is:

[0130]

[0131] In the formula, Sa t，k is the water supply threshold under the normal scenario in the kth unit in the tth year, m 3 ;Sa t，k，iis the threshold of water supply under the conventional scenario for the i-th water source in the k-th unit in the t-th year; I is the number of water sources, I=3, and when i=1,2...3, they are surface water, groundwater and unconventional water in that order.

[0132] Under normal scenarios, the threshold of water supply in each regional unit should be less than both the available amount of water resources and the control red line of water resources development and utilization. For river basins such as the Yellow River that use water consumption as a water resource requirement, the water consumption index should be converted into a water use index. Under long-series conditions, the available water supply of groundwater and unconventional water is usually not affected by rainfall and remains fixed, but the available water supply of surface water needs to be adjusted due to the influence of rainfall. It should be calculated based on the interannual changes in water use and the multi-year regulatory role of water conservancy projects. The specific calculation formula is:

[0133] Sa t，k，1 =Min(Sla t，k,1 ,Ra t，k,1 )

[0134]

[0135] Sa t,k,2 =Min(Sla t，k,2 ,Ra t，k，2 )

[0136] Sa t，k，3 =Ra t，k，3

[0137] In the formula, Sla t，k，1 For and Sla t，k，3 are the available surface water and groundwater in unit k in year t, m 3 ;Sa0 t,k,m is the natural runoff of the river in the kth unit in the mth month of the tth year, m 3 , m=1,2……M, M is the number of months; Sa1 t,k,m is the river ecological flow requirement for the mth month of the kth unit in the tth year, m 3 ;Sa2 t,k,x is the unusable amount of river flood in the kth unit in the xth month of the tth year, m 3 ; x1 and x2 are the start and end months of the river flood season in year t respectively; Ra t,k,1 , Ra t,k,2 and Ra t,k,3 They are the red line indicators for development and utilization of surface water, groundwater and unconventional water in the kth unit in the tth year. Under long series conditions, the indicator adopts the multi-year average indicator.

[0138] The future horizontal annual water supply threshold of each regional unit under the potential scenario refers to the water supply threshold determined by further considering the allocation and application of the reserved coordination indicators in a larger scope on the basis of the conventional scenario, that is, adding the reserved coordination indicators to the water supply threshold under the conventional scenario. If there are reserved coordination indicators in a larger scope, the water supply threshold under the potential scenario is greater than the water supply threshold under the conventional scenario; if there are no reserved coordination indicators, the water supply threshold under the potential scenario is equal to the water supply threshold under the conventional scenario. The specific calculation formula is:

[0139] Sb t,k,i =Sa t，k，i +T t，k，i ,

[0140]

[0141] In the formula, Sb t,k is the water supply threshold of the potential scenario in the kth unit in the tth year, m 3 ; Sb t,k,i is the threshold of available water volume for the i-th water source in the k-th unit in the t-th year under the potential scenario; T t,k,i is the basin reserve coordination index available for the i-th water source in the k-th unit in the t-th year, usually the surface water index (i.e., i = 1), m 3 .

[0142] Step 4: Carry out the design of double-layer nested water resource supply and demand combinations for each regional unit in future horizontal years.

[0143] Based on steps 2 and 3, a double-layer nested supply and demand combination design is carried out for each regional unit in the future horizontal year. The inner layer is the basic layer (i.e., the regional level), and the supply and demand constraint combination of each unit is the total water demand threshold (D t,k ) and the water supply threshold under normal circumstances (Sa t,k ); the outer layer is the expansion layer (i.e., the watershed level), and the supply and demand constraints of each unit are combined into the total water demand threshold under the condition of efficient water conservation (D t,k ) and the water supply threshold under potential scenarios (sb t,k As mentioned above, the inner and outer layers are separated by the basin reserved coordination index (T t,k ) for organic linking.

[0144] Step 5: Perform double-layer nested multi-water source multi-user multi-objective water resource optimization configuration calculation

[0145] Based on the design of the double-layer nested supply and demand combination in the future horizontal year of each regional unit, the multi-objective water resources optimization allocation is carried out in layers, mainly including the following steps:

[0146] Step 51: Determine the decision variables.

[0147] The decision variable of the basic layer is the allocation of water volume from different water sources to each user in each regional unit, i.e., Q t,k,i,j , represents the amount of water allocated from the i-th water source to the j-th user in the k-th unit in the t-th year, where t = 1~T; k = 1~K; i = 1~I; j = 1~J. The decision variable of the extended layer is the reserved water resources development and utilization index of the basin that can be obtained by the k-th unit (i.e., T t,k ). The decision variables of the basic layer and the extended layer can give the calculation results at the same time through the subsequent multi-objective optimization process.

[0148] Step 52: Set the objective function.

[0149] From the perspective of maximizing local management efficiency, the objective function of the basic layer is to maximize the economic efficiency of the regional unit, and the calculation formula is:

[0150] f t,a ={f1 t，k}

[0151]

[0152]

[0153] In the formula, f t,a is the objective function of the base layer in year t; f1 t，k is the economic objective function of the kth unit in the tth year, 10,000 yuan; Max() is the maximum value function; GDP t，k，j is the net economic output of the jth user in the kth unit in the tth year, 10,000 yuan; GEa t，k , GEb t，k , GGEC t，k and GEd t，k are the net economic output parameters of agriculture, industry, tertiary industry and living sectors brought by the k-th unit of water use in year t, 10,000 yuan / m 3 ; U t0,k，j is the water consumption of the jth department in the kth unit in the current year, fa, ib, fc, and fd are the allocation coefficients of agriculture, industry, tertiary industry, and living sectors respectively; GEa t0，k ,GEb t0，k , GEC t0，k They are respectively the added value of agriculture, industry and tertiary industry brought by the water use of the kth unit in the current year, 10,000 yuan; GEd t0,k is the disposable income of residents in the kth unit in the current year, ten thousand yuan; er is the Engel coefficient, dimensionless.

[0154] From the perspective of optimizing the comprehensive efficiency of the overall water resources management of the basin, the objective function of the expansion layer is to maximize the economic efficiency of water resources utilization, the balance of development level, and the balance of social equity in the basin (regional unit as a whole). The calculation formula of the objective function of the expansion layer is as follows:

[0155] f t，b ={f1 t , f2 t , f3 t}

[0156] In the formula, f t，b f1 is the objective function of the expansion layer in year t; t f2 is the economic objective function in year t; t f3 is the objective function of the development level balance in year t; t is the social equity equilibrium objective function in year t.

[0157] 1) Economic target: The economic target is to maximize the per capita added value of all units in the basin. The calculation formula is:

[0158]

[0159]

[0160] In the formula, POP t,k is the population of unit k in year t, people; GDP t,k is the added value of the kth unit in the tth year, ten thousand yuan.

[0161] 2) Development level balance target: The development level balance target is to minimize the difference in per capita added value brought about by the development and utilization of water resources in each unit. The Gini coefficient method is used for calculation, with the maximum being "1" and the minimum being "0". The closer it is to 0, the stronger the balance of the development level. The calculation formula is as follows:

[0162] f2 t =Min(Gn t )

[0163]

[0164] In the formula, Gn t is the Gini coefficient of per capita net economic output of all units in year t, dimensionless; GDPR k POPR is the proportion of the net economic output of the kth unit in the tth year to the total net economic output, dimensionless; k POPL is the proportion of the population of the kth unit in the tth year to the total population, dimensionless; kIt is the cumulative proportion of the population of the kth unit to the total population (arranged in ascending order of per capita value added), dimensionless.

[0165] 3) Social equity and balance goal: The dispersion coefficient of water shortage rate is used to measure the balance of social equity, that is, the dispersion coefficient of the maximum water shortage rate in each region is the smallest. The mathematical calculation formula of the dispersion coefficient of water shortage rate (also called coefficient of variation) is as follows:

[0166] f3 t =Min(Rd t )

[0167]

[0168]

[0169] In the formula, Rd t Sd is the dispersion coefficient of water shortage rate of each unit in year t, dimensionless. t is the average water shortage rate of each unit in the tth year, %; Td t is the standard deviation of water shortage rate of each unit in year t, %.

[0170] Step 53: Determine the constraints.

[0171] The constraints mainly include water demand constraints of each regional unit, water supply constraints under conventional scenarios, water supply constraints under potential scenarios, ecological flow guarantee constraints, water quality compliance constraints in water functional areas, and non-negative constraints, as follows:

[0172] 1) Water demand constraint: The water volume configured for the jth user in each unit should not be greater than the water demand of the jth user in each unit under the condition of efficient water saving. The specific calculation formula is as follows:

[0173]

[0174] 2) Water supply constraints under normal scenarios: The configured water volume of the i-th water source in each unit should not be greater than the water supply threshold of each water source in each unit under normal scenarios. The specific calculation formula is as follows:

[0175]

[0176] 3) Water supply constraints under potential scenarios: The water volume allocated to each water source in each unit plus the water resources development and utilization indicators reserved in the basin should not be greater than the water supply threshold of each water source in each unit under the potential scenario. The specific calculation formula is as follows:

[0177]

[0178] 4) Ecological flow guarantee constraint: The water consumption of each user in the kth unit in the tth year after the allocation of water should meet the requirements of the ecological flow of the main control section of the river. The specific calculation is as follows:

[0179]

[0180] Where Efl k,t,h is the ecological flow control requirement of the hth section in the kth unit in the tth year, m 3 / s; Eek t,k is the water consumption coefficient of the kth unit in the tth year, dimensionless; h1 is the total number of upstream unit numbers related to the hth section; We t,k,h1 is the discharge requirement of the upstream control section h1, m 3 / s.

[0181] 5) Constraints on water quality compliance in water functional areas: Pollutants discharged into water functional areas should meet the constraints on pollutants that can be accommodated in the water functional areas, as shown in the following formula:

[0182]

[0183] In the formula, WR t,m,n is the controlled amount of pollutants entering the river in the nth water function zone m in the tth year, t / a; R t,k,j,m is the pollutant emission coefficient of the mth pollutant of the jth user in the kth unit (discharging into the nth water functional area) in the tth year, dimensionless; C t,k,j,m is the concentration of the mth pollutant of the jth user in the kth unit in the tth year, mg / l;

[0184] 6) Non-negative constraint: The amount of water allocated from different water sources in each regional unit to each user should not be negative, as shown in the following formula:

[0185] Q t,k,i,j ≥0

[0186] Step 54: Solve using an efficient optimization algorithm.

[0187] The non-dominated sorting genetic algorithm with elite strategy (NSGA-II) is used to achieve efficient optimization, which mainly includes the following steps:

[0188] 1) Data input: Input the data and main parameters of the non-dominated sorting genetic algorithm with elite strategy, such as objective function, population size, genetic generation, crossover rate and mutation rate, etc.;

[0189] 2) Initialize the population and generate the parent population: use a random generation method for the initial values ​​of the decision variables;

[0190] 3) Perform non-dominated sorting and objective function fitness calculation: Initialize the population, calculate the fitness of the objective function of the population, and perform fast non-dominated sorting so that the chromosome gene encoding of the decision variable with high objective function fitness is preserved, and the solution with low fitness is crossover and mutation to generate new offspring to meet the elite strategy, that is, the parent and offspring compete, and the chromosome gene encoding of the decision variable that best meets the objective function is selected and preserved. By increasing the crowding degree and improving the population diversity, the optimization efficiency of the algorithm is improved;

[0191] 4) Circular calculation retains elite individuals to obtain the Pareto frontier: the parent and offspring populations are mixed and cyclically calculated to perform crossover, mutation, non-dominated sorting and fitness calculation, and elite individuals with high fitness of the objective function are retained until the genetic algebra conditions are met and the Pareto frontier of the decision variable is obtained;

[0192] 5) Give the optimal solution based on the objective function weight: According to the Pareto frontier, determine the objective function weight and recommend the optimal allocation solution for water resources with multiple water sources and multiple users.

[0193] Step 6: Adjust the economic and social characteristic parameters of each unit in the future horizontal year and determine the optimal control plan.

[0194] According to the long series of water sources and users in each regional unit (that is, the configured water volume Q obtained by optimization solution t,k,i,j ), calculate the water intake guarantee rate by user, as follows:

[0195]

[0196]

[0197] Where P k,a is the water supply guarantee rate of agricultural users in unit k, %, PL k，a The water supply guarantee rate requirement for agricultural users in unit k is usually greater than 50% or 75%; k,b is the water supply guarantee rate of the kth unit industrial user, %; PL k，b The water supply guarantee rate requirement for the kth unit industrial user is usually greater than 90% or 95%; P k，c is the water supply guarantee rate of residents in unit k, %; PL k,c The water supply guarantee rate requirement for the residential users in unit k is usually required to be greater than 95% or 98%; P k,d is the water supply guarantee rate of the kth unit ecological user, %; PL k,d The water supply guarantee rate requirement for the kth unit ecological user is usually required to be greater than 50% or 75%.

[0198] If the water withdrawal guarantee rate requirement is not met, it is necessary to adjust the economic and social characteristic parameters of each unit in the future horizontal year, and repeat the above steps 2 to 5 until the configured water volume of each user in each unit meets the water withdrawal guarantee rate requirement, as follows:

[0199] G1 k ′=G1 k ×Min(K1 t，k ,M1 t，k ,)

[0200] G2 k ′=G2 k ×Min(K2 t，k , M2 t，k ,)

[0201] G3 k ′=G3 k ×Min(K3 t，k , M3 t，k ,)

[0202] G4 k ′=G4 k ×Min(K4 t，k , M4 t，k ,)

[0203] G5 k ′=G5 k ×Min(K5 t，k , M5 t，k ,)

[0204] G6 k ′=G6 k ×Min(K6 t，k , M6 t，k ,)

[0205] G7 k ′=G7 k ×Min(K7 t，k , M7 t，k ,)

[0206] In the formula, G1 k ′~G7 k ′ are the adjusted values ​​of urban population, rural population, industrial added value, effective irrigation area of ​​farmland, irrigation area of ​​forest and fruit, water replenishment area of ​​fish ponds and number of livestock in the kth unit in the tth year; K1 t,k ~K7 t，k M1 is the adjustment coefficient of urban population, rural population, industrial added value, effective irrigation area of ​​farmland, forest and fruit irrigation area, fish pond replenishment area, and livestock number of unit k in year t, dimensionless; t,k ~M7 t，kThey are the maximum limit rate requirements for urban population, rural population, industrial added value, effective irrigation area of ​​farmland, forestry and fruit irrigation area, fish pond replenishment area, and livestock number at the k-th unit management level in the t-th year, dimensionless.

[0207] Embodiment 1

[0208] This embodiment is an application example of the above method.

[0209] This embodiment uses the Yellow River Basin in Gansu Province as the research basin, and selects 9 prefectures (states) involved in the basin as basic regional units (namely Wuwei City, Lanzhou City, Baiyin City, Linxia Prefecture, Dingxi City, Tianshui City, Pingliang City, Qingyang City and Gannan Prefecture). 2030 is selected as the future horizontal year, and 1956-2022 is selected for long series year-on-year calculation. The data comes from the "Gansu Province Industry Water Use Quota (2023 Edition)", the water resources bulletin of various cities in the Yellow River Basin of Gansu Province, the Economic and Social Statistical Yearbook, the Water Conservancy Statistical Yearbook, and the water resources and water ecological protection plan. The calculation results of the water demand threshold, water supply threshold and multi-source-multi-user multi-objective optimization configuration of each regional unit in the basin without considering the basin coordination index in the future horizontal year are shown in Table 1.

[0210] Table 1 Water demand, available water and allocation results of each regional unit in the basin in the future horizontal year (no overall planning, long series multi-year average)

[0211]

[0212] In the calculation part of double-layer nested multi-water source multi-user multi-objective water resources optimization allocation, the selected population size is 2000 (50 generations), and the calculation results are basically stable. Based on the red line constraints of water resources development and utilization in each region, the overall allocation index of the basin is considered to be 162 million m 3 .

[0213] Figure 3The Pareto frontier obtained by optimizing the solution with the non-dominated sorting genetic algorithm with elite strategy is given, and the selectable satisfactory solutions (solutions B-E) and the recommended satisfactory solution (solution A) are given. It can be seen that the Gini coefficient, water shortage dispersion coefficient and per capita GDP of solution A are all small, that is, the development level balance and social equity balance goals are good, and the economic goal is poor, which is the recommended satisfactory solution; compared with solution A, solution B has a reduced Gini coefficient, and the water shortage dispersion coefficient and per capita GDP level are increased, that is, the development level balance and economic goals are improved, but the social equity balance goal is reduced. Compared with solution B, solution C has an increased per capita GDP, a reduced Gini coefficient, and an increased water shortage dispersion coefficient, that is, the economic and development level balance goals are further improved, but the social equity balance goal is further reduced. Compared with solution C, solution D has a reduced per capita GDP, an increased Gini coefficient, and a reduced water shortage dispersion coefficient, that is, the social equity balance goal is improved, but the development level balance and economic goals are reduced. Compared with solution D, solution E has a further reduction in GDP per capita, and the coefficient of dispersion of water shortage and the Gini coefficient are significantly reduced, that is, the economic goal is improved, but the development level balance and social equity balance goals are reduced. In fact, according to the management goal requirements of managers with different preferences at different times, the satisfactory solutions on the Pareto front surface given in the figure can be selected. Each solution has different objective function characteristics and corresponds to different basin coordination indicator allocation schemes. In general, the Pareto front surface composed of satisfactory solutions obtained through double-layer nested multi-water source, multi-user and multi-objective water resources optimization allocation calculation can provide quantitative technical support for basin and regional water resources management planning, policy introduction, and related water conservancy project construction and management evaluation.

[0214] Figure 4 The changes of each objective function with generations are given, and the red line is the mean of the objective function of each generation of samples. It can be seen that the mean of the per capita GDP indicator has increased in the fluctuation, and the mean of the Gini coefficient and the water shortage rate dispersion coefficient has decreased in the fluctuation, that is, multiple objectives such as economic efficiency, development level balance and social equity balance have been significantly improved, and the comprehensive allocation and coordinated management capabilities of regional and river basin water resources have been continuously improved.

[0215] Considering the economic goal (f1 t ), development level balance goal (f2 t ), social equity and balance (f3 t ) target, the application results of the basin coordination indicators in a larger scope (satisfactory solution A) are as follows Figure 5 As shown in the figure, Qingyang City, Lanzhou City, Gannan Prefecture and Tianshui City received relatively large support indicators, accounting for 22.0%, 20.8%, 18.6% and 14.1% of the total coordinated indicators respectively, with more provincial coordinated indicator support.

[0216] Table 2 compares the objective function based on the double-layer nested configuration and the adjustment values ​​of the characteristic parameters of economic and social development with and without the basin coordination indicators.

[0217] Table 2 Comparison of objective functions based on double-layer nested configuration (with / without basin coordination indicators, long series multi-year average)

[0218] index No coordination There is a coordinated Rate of change (%) GDP per capita (10,000 yuan / person) 5.96 6.23 4.53 Gini coefficient (dimensionless) 0.24 0.21 -12.50 Water shortage rate dispersion coefficient (dimensionless) 0.85 0.84 -1.18 Industrial added value (100 million yuan) 2894.7 2932.2 1.30 Effective irrigation area of ​​farmland (ten thousand mu) 460.4 485.5 5.45 Irrigated area of ​​forest and fruit trees (ten thousand mu) 119.4 123.8 3.69

[0219] For the satisfactory solution A, when considering the basin coordination indicators, the per capita GDP index increased by 4.52%, and the Gini coefficient and water shortage dispersion coefficient index decreased by 12.24% and 1.24% respectively, indicating that the optimal configuration of basin coordination indicators has significantly promoted the improvement of multi-objective management efficiency such as economic efficiency, development level balance and social equity balance. Similarly, the socio-economic characteristic parameters are significantly improved when considering basin coordination indicators.

[0220] Finally, it should be noted that the above is only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred arrangement scheme, a person skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A water resource rigid constraint and balance control method based on double-layer nested configuration, characterized in that: The method comprises the following steps: Step 1: Divide the regional units and determine their economic and social characteristic parameters for the future horizontal year: Based on the characteristics of water resources and their development and utilization in the study basin, the total population and industrial development, structure and trend, and administrative division factors, combined with the objectives and requirements of basin and regional water resources management, the study basin is divided into several independent regional units, and the economic and social characteristic parameters of each regional unit in the future level year are determined; the economic and social characteristic parameters include urban population, rural population, industrial added value, effective irrigation area of ​​farmland, forest and fruit irrigation area, fish pond water replenishment area, and the number of large and small livestock; Step 2: Calculate the water demand threshold of each regional unit under the condition of high-efficiency water saving for a long series of years: Based on the economic and social characteristic parameters determined in step 1, combined with the water use indicators under the condition of efficient water conservation, the long series calculates the water demand of each regional unit under the condition of efficient water conservation in the future horizontal year year by year. The specific calculation formula is: D t，k，1 =G1 k ×L1 k ×0.365 D t，k，2 =G1 k ×L2 k ×0.365 D t，k，3 =G1 t，k ×L3 t，k D t，k，4 =G2 k ×L4 k ×0.365 D t，k，5 =G3 k ×L5 t，k D t，k，6 =G4 k ×L6 t，k D t，k，7 =G5 k ×L7 t，k D t，k，8 =G6 k ×L8 t，k D t，k，9 =G7 k ×L9 k Where D t，k is the total water demand threshold of the kth unit in year t, m 3 ;D t，k，j is the water demand threshold of the jth user in the kth unit in the tth year, m 3 ; k = 1, 2...K, that is, there are K different regional units; t = 1, 2...T, that is, there are T future horizontal years, such as short-term, medium-term and long-term; J is the number of water users, that is, J = 9; j = 1, 2...9, in order of urban residents, urban public, ecological environment, rural residents, industrial water, farmland irrigation, forestry and fruit irrigation, aquaculture and livestock and poultry breeding; G1 k is the urban population of the kth unit, people; G2 k is the rural population of the kth unit, people; G3 k is the industrial added value of the kth unit, ten thousand yuan; G4 k is the effective irrigation area of ​​farmland in unit k, mu; G5 k is the forest and fruit irrigation area of ​​the kth unit, mu; G6 k is the water replenishment area of ​​the fish pond in unit k, mu; G7 k is the number of livestock in the kth unit, head; L1 k L2 is the per capita water consumption index of urban residents, L / person / day; k is the urban public per capita water consumption index, L / person / day; L4 t，k is the per capita water use index in rural areas, L / person / day; L5 t，k It is the water consumption index per 10,000 yuan of industrial added value, m 3 / 10,000 yuan; L9 t，k L3 is the livestock water use index, L / head / day; t，k is the per capita ecological environment water use index, m 3 / person, L6 t，k 、L7 t，k and L8 t，k They are the net quota indicators per unit area for farmland irrigation, forest and fruit land, and fish pond water replenishment, m 3 / mu; Step 3: Calculate the water supply thresholds of each regional unit under the conventional and potential scenarios in the future horizontal year: Under the conventional scenario, the threshold of the future horizontal annual water supply of each regional unit is determined by comprehensively considering the water resources endowment, water resources development and utilization status, water conservancy project construction and related water resources management requirements. It is specifically divided into three categories: surface water, groundwater and unconventional water. The surface water includes local water, transit water and external water. The specific calculation formula is: In the formula, Sa t，k is the water supply threshold under the normal scenario in the kth unit in the tth year, m 3 ;Sa t，k，i is the threshold of water supply under the conventional scenario for the i-th water source in the k-th unit in the t-th year; I is the number of water sources, I=3, i=1, 2…3, in order, it is surface water, groundwater, and unconventional water; Under the conventional scenario, the threshold of the future horizontal annual water supply of each regional unit is less than the available amount of water resources and the control red line of water resources development and utilization. The specific calculation formula is: Saddle t，k，1 =Min(Sla t，k，1 ,Ra t，k，1 ) Saddle t，k，2 =Min(Sla t，k，2 ,Ra t，k，2 ) on t，k，3 =Ra t，k，3 In the formula, Sla t，k，1 For and Sla t，k，3 are the available surface water and groundwater in unit k in year t, m 3 ;Sa0 t，k，m is the natural runoff of the river in the kth unit in the mth month of the tth year, m 3 , m=1,2.....M, M is the number of months; Sa1 t，k，m is the river ecological flow requirement for the mth month of the kth unit in the tth year, m 3 ;Sa2 t，k，x is the unusable amount of river flood in the kth unit in the xth month of the tth year, m 3 ; x1 and x2 are the start and end months of the river flood season in year t respectively; Ra t，k，1 , Ra t，k，2 and Ra t，k，3 They are the red line indicators of water resources development and utilization of surface water, groundwater and unconventional water in the kth unit in the tth year. Under the long series conditions, this indicator adopts the multi-year average indicator; The future horizontal annual water supply threshold of each regional unit under the potential scenario refers to the water supply threshold determined by considering the allocation and application of the reserved overall planning indicators in a larger scope on the basis of the conventional scenario, that is, the reserved overall planning indicators are added to the water supply threshold under the conventional scenario. The specific calculation formula is: Sb t，k，i =In t，k，i +T t，k，i In the formula, Sb t，k is the water supply threshold of the potential scenario in the kth unit in the tth year, m 3 ; Sb t，k，i is the threshold of available water volume for the i-th water source in the k-th unit in the t-th year under the potential scenario; T t，k，i The reserve overall index for the watershed that can be obtained from the i-th water source in the k-th unit in the t-th year, m 3 ; Step 4: Carry out the design of double-layer nested water resource supply and demand combinations for each regional unit in the future horizontal year: On the basis of steps 2 and 3, a two-layer nested supply and demand combination design is carried out for each regional unit in the future horizontal year. The inner layer is the basic layer, i.e., the regional level. The supply and demand constraint combination of each unit is the total water demand threshold under the condition of efficient water conservation and the water supply threshold under the conventional scenario. The outer layer is the extended layer, i.e., the basin level. The supply and demand constraint combination of each unit is the total water demand threshold under the condition of efficient water conservation and the water supply threshold under the potential scenario. The inner layer and the outer layer are organically linked through the basin reserved coordination indicators. Step 5: Perform double-layer nested multi-water source multi-user multi-objective water resource optimization configuration calculation: Based on the design of the double-layer nested supply and demand combination in the future horizontal year of each regional unit, the multi-objective water resources optimization allocation is carried out in layers, mainly including the following steps: Step 51: Determine the decision variables: The decision variable of the basic layer is the allocation of water volume from different water sources to each user in each regional unit, i.e., Q t，k，i，j , represents the amount of water allocated from the i-th water source to the j-th user in the k-th unit in the t-th year, where t = 1 ~ T; k = 1 ~ K; i = 1 ~ I; j = 1 ~ J; the decision variable of the extended layer is the water resources development and utilization index reserved for the basin that can be obtained by the k-th unit; Step 52: Set the objective function: The objective function of the base layer is to maximize the economic efficiency of the regional unit, and the calculation formula is: f t，a ={f1 t，k } In the formula, f t，a is the objective function of the base layer in year t; f1 t，k is the economic objective function of the kth unit in the tth year, 10,000 yuan; Max() is the maximum value function; GDP t，k，j is the net economic output of the jth user in the kth unit in the tth year, 10,000 yuan; GEa t，k , GEb t，k ,GEc t，k and GEd t，k are the net economic output parameters of agriculture, industry, tertiary industry and living sectors brought by the k-th unit of water use in year t, 10,000 yuan / m 3 ; U t0，k，j is the water consumption of the jth department in the kth unit in the current year, fa, fb, fc, and fd are the allocation coefficients of agriculture, industry, tertiary industry, and living sectors respectively; GEa t0，k , GEb t0，k ,GEc t0，k They are respectively the added value of agriculture, industry and tertiary industry brought by the water use of the kth unit in the current year, 10,000 yuan; GEd t0，k is the disposable income of residents in the kth unit in the current year, ten thousand yuan; er is the Engel coefficient, dimensionless; The objective function of the extended layer is to maximize the economic efficiency of water resources utilization in the basin, maximize the balance of development level, and maximize the balance of social equity. The calculation formula of the objective function of the extended layer is as follows: <h2 style=";text-align:left;direction:ltr">f<h2 style=";text-align:left;direction:ltr"> t，b <h2 style=";text-align:left;direction:ltr"> ={f1<h2 style=";text-align:left;direction:ltr"> t <h2 style=";text-align:left;direction:ltr"> f2<h2 style=";text-align:left;direction:ltr"> t <h2 style=";text-align:left;direction:ltr"> f3<h2 style=";text-align:left;direction:ltr"> t <h2 style=";text-align:left;direction:ltr">} In the formula, f t，b f1 is the objective function of the expansion layer in year t; t f2 is the economic objective function in year t; t f3 is the objective function of the development level balance in year t; t is the social equity equilibrium objective function in year t; Step 53: Determine the constraints: Determine the constraints, which include water demand constraints of each regional unit, water supply constraints under conventional scenarios, water supply constraints under potential scenarios, ecological flow guarantee constraints, water quality compliance constraints in water functional areas, and non-negative constraints; Step 54: Solve using an efficient optimization algorithm: The non-dominated sorting genetic algorithm with elite strategy is used to achieve efficient optimization and provide an optimal allocation scheme for water resources with multiple water sources and multiple users. Step 6: Adjust the economic and social characteristic parameters of each unit in the future horizontal year and determine the optimal control plan: According to the long series of water sources and users in each regional unit, the configured water volume Q is obtained through optimization solution. t，k，i，j , calculate the water intake guarantee rate by user, the specific calculation formula is: Where P k，a is the water supply guarantee rate of agricultural users in unit k, %, PL k，a is the water supply guarantee rate requirement for agricultural users in unit k, which is greater than 50% or 75%; P k，b is the water supply guarantee rate of the kth unit industrial user, %; PL k，b The water supply guarantee rate requirement for the kth unit industrial user is greater than 90% or 95%; P k，c is the water supply guarantee rate of residents in unit k, %; PL k，c The water supply guarantee rate requirement for the kth unit residential users is required to be greater than 95% or 98%; P k，d is the water supply guarantee rate of the kth unit ecological user, %; PL k，d The water supply guarantee rate requirement for the ecological user in unit k is greater than 50% or 75%; If the water withdrawal guarantee rate requirement is not met, the economic and social characteristic parameters of each unit in the future horizontal year are adjusted, and the above steps 2 to 5 are repeated until the configured water volume of each user in each unit meets the water withdrawal guarantee rate requirement. The specific calculation formula is: G1 k ′=G1 k ×Min(K1 t，k ,M1 t，k ,) <h2 style=";text-align:left;direction:ltr">G2<h2 style=";text-align:left;direction:ltr"> k <h2 style=";text-align:left;direction:ltr"> ′=G2<h2 style=";text-align:left;direction:ltr"> k <h2 style=";text-align:left;direction:ltr"> ×Min(K2<h2 style=";text-align:left;direction:ltr"> t，k <h2 style=";text-align:left;direction:ltr"> M2<h2 style=";text-align:left;direction:ltr"> t，k <h2 style=";text-align:left;direction:ltr"> ,) <h2 style=";text-align:left;direction:ltr">G3<h2 style=";text-align:left;direction:ltr"> k <h2 style=";text-align:left;direction:ltr"> ′=G3<h2 style=";text-align:left;direction:ltr"> k <h2 style=";text-align:left;direction:ltr"> ×Min(K3<h2 style=";text-align:left;direction:ltr"> t，k <h2 style=";text-align:left;direction:ltr"> M3<h2 style=";text-align:left;direction:ltr"> t，k <h2 style=";text-align:left;direction:ltr"> ,) G4 k ′=G4 k ×Min(K4 t，k ,M4 t，k ,) G5 k ′=G5 k ×Min(K5 t，k ,M5 t，k ,) G6 k ′=G6 k ×Min(K6 t，k ,M6 t，k ,) G7 k ′=G7 k ×Min(K7 t，k ,M7 t，k ,) In the formula, G1 k ′~G7 k ′ are the adjusted values ​​of urban population, rural population, industrial added value, effective irrigation area of ​​farmland, irrigation area of ​​forest and fruit, water replenishment area of ​​fish ponds and number of livestock in the kth unit in the tth year; K1 t，k ~K7 t，k M1 is the adjustment coefficient of urban population, rural population, industrial added value, effective irrigation area of ​​farmland, forest and fruit irrigation area, fish pond replenishment area, and livestock number of unit k in year t, dimensionless; t，k ~M7 t，k They are the maximum limit rate requirements for urban population, rural population, industrial added value, effective irrigation area of ​​farmland, forestry and fruit irrigation area, fish pond replenishment area, and livestock number at the k-th unit management level in the t-th year, dimensionless.

2. According to claim 1, a water resource rigid constraint and balance control method based on double-layer nested configuration is characterized in that: The regional units described in step 1 are divided according to administrative divisions, including provincial, prefectural, district, county, and township administrative units.

3. According to claim 2, a water resource rigid constraint and balance control method based on double-layer nested configuration is characterized in that: The specific method for determining the economic and social characteristic parameters of each regional unit in the future horizontal year described in step 1 is: to determine according to the relevant planning data of the economic and social characteristic parameters of each regional unit, and for the lack of relevant planning data, to conduct forecast analysis based on relevant historical data, the historical data include water resources bulletin, economic and social statistical yearbook, water conservancy development bulletin; the forecast analysis includes two methods, one is the historical trend extension method, that is, based on historical data, identify the influencing factors, and predict the values ​​of various parameters in the future horizontal year through multivariate regression technology; the other is the comprehensive simulation method, based on the identification of influencing factors, by establishing a mathematical model to predict the values ​​of the economic and social characteristic parameters of each regional unit in the future horizontal year, the mathematical model is a system dynamics model, a fuzzy analysis model or a neural network model.

4. The method for rigid constraint and balance control of water resources based on double-layer nested configuration according to claim 1 is characterized in that: The water use index described in step 2 is calculated according to the historical trend method, or determined by referring to the "Technical Specifications for Forecasting and Analysis of Water Resources Supply and Demand" and the water use quotas issued by the state or provinces, autonomous regions, and municipalities directly under the central government; the water use index includes two types: one is the life and industrial type indicators, including the per capita water use index of urban residents, the per capita water use index of urban public, the per capita water use index of rural areas, the water use index of industrial ten thousand yuan of added value, and the livestock water use index; the second is the ecological and agricultural type indicators, including the per capita ecological environment water use index, the net quota index per unit area of ​​farmland irrigation, forest and fruit land, and fish pond water replenishment; the life and industrial type indicators are not affected by rainfall and take fixed values; the ecological and agricultural type indicators are affected by rainfall and need to be adjusted, specifically, in a wet year, a water use index with a higher agricultural water demand guarantee rate is selected, and in a dry year, a water use index with a lower guarantee rate is selected.

5. The method for rigid constraint and balance control of water resources based on double-layer nested configuration according to claim 1 is characterized in that: The economic objective in step 52 is to maximize the per capita added value of all units in the basin, and the calculation formula is: In the formula, POP t，k is the population of unit k in year t, people; GDP t，k is the added value of the kth unit in year t, ten thousand yuan; The development level balance target is to minimize the difference in per capita added value brought about by the development and utilization of water resources in each unit; the Gini coefficient method is used for calculation, and the calculation formula is: f2 t =Min(Gn t ) In the formula, Gn t is the Gini coefficient of per capita net economic output of all units in year t, dimensionless; GDPR k POPR is the proportion of the net economic output of the kth unit in the tth year to the total net economic output, dimensionless; k POPL is the proportion of the population of the kth unit in the tth year to the total population, dimensionless; k is the cumulative proportion of the population of the kth unit to the total population, dimensionless; The social equity and balance goal is measured by the dispersion coefficient of water shortage rate, that is, the dispersion coefficient of the maximum water shortage rate in each region is the smallest; the calculation formula of the dispersion coefficient of water shortage rate is: <h2 style=";text-align:left;direction:ltr">f3<h2 style=";text-align:left;direction:ltr"> t <h2 style=";text-align:left;direction:ltr"> =Min(Rd<h2 style=";text-align:left;direction:ltr"> t <h2 style=";text-align:left;direction:ltr"> ) Where Rd t is the dispersion coefficient of water shortage rate of each unit in year t, dimensionless; Sd t is the average water shortage rate of each unit in the tth year, %; Td t is the standard deviation of water shortage rate of each unit in year t, %.

6. The method for rigid constraint and balance control of water resources based on double-layer nested configuration according to claim 1 is characterized in that: The water demand constraint in step 53 is: the water volume configured for the j-th user in each unit is not greater than the water demand under the condition of efficient water saving for the j-th user in each unit, and the calculation formula is: The water supply constraint under the conventional scenario is: the configured water volume of the i-th water source of each unit is not greater than the water supply threshold of each water source in each unit under the conventional scenario, and the calculation formula is: The water supply constraint under the potential scenario is: the water allocation of each water source in each unit plus the reserved overall planning index of the basin shall not be greater than the water supply threshold of each water source in each unit under the potential scenario. The calculation formula is: The ecological flow guarantee constraint is: the water consumption of each user in the kth unit in the tth year after the configured water volume meets the requirements of the ecological flow of the river control section, and the calculation formula is: Where Efl k，t，h is the ecological flow control requirement of the hth section in the kth unit in the tth year, m 3 / s; Eek t，k is the water consumption coefficient of the kth unit in the tth year, dimensionless; h1 is the total number of upstream unit numbers related to the hth section; We t，k，h1 is the discharge requirement of the upstream control section h1, m 3 / s; The water quality compliance constraint of the water functional zone is: the pollutants discharged into the water functional zone meet the pollutant constraints that the water functional zone can accommodate, and the calculation formula is: In the formula, WR t，m，n is the controlled amount of pollutants entering the river in the nth water function zone m in the tth year, t / a; R t，k，j，m is the pollutant emission coefficient of the mth pollutant discharged by the jth user of the nth water functional area from the kth unit in the tth year, dimensionless; C t，k，j，m is the concentration of the mth pollutant of the jth user in the kth unit in the tth year, mg / l; The non-negative constraint is that the configured water volume from different water sources in each regional unit to each user is not negative, and the calculation formula is: Q t，k，i，j ≥0。 7. The method for rigid constraint and balance control of water resources based on double-layer nested configuration according to claim 1 is characterized in that: The method of using the non-dominated sorting genetic algorithm with an elite strategy to achieve efficient optimization in step 54 specifically includes the following steps: 1) Data input: Input the data and parameters of the non-dominated sorting genetic algorithm with elite strategy, including objective function, population size, genetic generation, crossover rate and mutation rate; 2) Initialize the population and generate the parent population: use a random generation method for the initial values ​​of the decision variables; 3) Perform non-dominated sorting and objective function fitness calculation: Initialize the population, calculate the fitness of the objective function, and perform fast non-dominated sorting so that the chromosome gene encoding of the decision variable with high objective function fitness is preserved, and the solution with low fitness is crossover and mutation to generate new offspring to meet the elite strategy, that is, the parent and offspring compete, and the chromosome gene encoding of the decision variable that best meets the objective function is selected and retained. By increasing the crowding degree and improving the population diversity, the optimization efficiency of the algorithm is improved; 4) Circular calculation retains elite individuals to obtain the Pareto frontier: the parent and offspring populations are mixed and cyclically calculated to perform crossover, mutation, non-dominated sorting and fitness calculation, and elite individuals with high fitness of the objective function are retained until the genetic algebra conditions are met and the Pareto frontier of the decision variable is obtained; 5) Give the optimal solution based on the objective function weight: According to the Pareto frontier, determine the objective function weight and recommend the optimal allocation solution for water resources with multiple water sources and multiple users.

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